The term 'Sing Like a Bird' can be broken down into three crossword solutions: TRILL (5 letters), WARBLE (6 letters), and Tweedle (7 letters). Trilling is a vocal technique that involves rapidly repeating a single note or syllable, often used to imitate the sound of birds. Warbling is a type of singing that involves alternating between two notes, usually in a melodic pattern. Tweedling is a type of singing that involves rapidly alternating between two notes, usually in a more staccato pattern than warbling. All three techniques are used to imitate the sound of birds singing.